Help choosing cob's for a converted marsII 900W

Hello guys,

I am converting a mars II 900w (5W epistar chips) after a lot of headaches with it, and I am not sure what to go for.
The specs are:
Mars 2 900W 5w chips. 9 drivers inside: Voltage max 112v. Amperage max 0.71Amp also 4 fans at 12V 0.2 amp
My growing space is 0.7m wide x 0.8m deep x 2m high.
I've got the aluminium piece cut to size, cables,soldering station,thermal paste,etc... But I can't decide if to go for soft Amp vero's 29, try a citizen c.o.b. or go for soft Amp cree 3590 or 3070, (but the price of it and it's availability in Europe is a problem) .
It will be mainly for flower as I just grow autos and I veg them in the lower shelf with a mix of CFL +T5

Thanks for the help!

what are the specifics for each driver. you could use some lower wattage cobs like the Vero's are a good choice. peace

The drivers are generic, they are inside a black plastic box and don't have any specs or labels on it, I tested myself and the results are 112V and 0.7 amp. I recon theya are 50V-110V 0.71Amp drivers.
Vero 29 is one of my options ,yes!

For max light for minimal cost...

Each driver: 3x Citizen CLU046-1212 3500k in series.

Total 27 COBs would cost around $300.

Should give you around 700w of awesomeness. Would be equivalent to a 1000w DE HPS but with 30% less heat.

loftygoals said:

For max light for minimal cost...

Each driver: 3x Citizen CLU046-1212 3500k in series.

Total 27 COBs would cost around $300.

Should give you around 700w of awesomeness. Would be equivalent to a 1000w DE HPS but with 30% less heat.

Click to expand...

Hi Sir!
Thanks for the answer, but it won't be too much for my box? 0.7m x 0.8m 2m high

I am almost convinced to go for 6 cbx3590 72V 3500K with holders and glass lens 80 at 700mA

Thanks for the info regardless!

All in the door for 220 british pounds, not bad no?

BuscaLuz said:

Hi Sir!
Thanks for the answer, but it won't be too much for my box? 0.7m x 0.8m 2m high

I am almost convinced to go for 6 cbx3590 72V 3500K with holders and glass lens 80 at 700mA

Thanks for the info regardless!

All in the door for 220 british pounds, not bad no?

Click to expand...

Lol, yes it would be waaay too much for 0.7x0.8! Sorry, I was just trying to give you the highest light output using your drivers and didn't see your area in the OP.

You have 0.56 sqm. If you went with CXB3590 72V at 0.7A they'd be running around 50w each and putting out around 2.62 umol/w. If you had 6 of them then (6x50x2.62)/0.56=1403umol/sqm.

That is right on the max light output for your area. Pretty much perfect.

Thanks again for your answer sir!
Any technical data that reassure my decision is very welcome.

Have a good smoke!